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Papers Posted on - Nov / 2012

Author Name

N. Kishore Nath

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Paper Title

Characterization of Rayon Carbon Phenolic Composite as Ablative Liner

Abstract
The Rayon carbon fabric with thickness of 0.4 to 0.5 mm is impregnated with phenolic resin. The laminate characterization is done in terms of physical mechanical and thermal properties. The physical properties like density, fibre and resin content, barcol hardness. The thermal properties like Oxy-acetylene torch test to estimate erosion rate. The mechanical properties like tensile strength and modulus, Compression strength and modulus, flexural strength & modulus, In-plane shear strength and modulus, ILSS etc. This paper briefs about the physical, mechanical and thermal tests conducted on the laminate to qualify this material for use as ablative liner for Solid Rocket Nozzles.

Abstract
This paper presents a review about several aspects of preparation & usage of carbon nanotubes. Several aspects of preparation of Doped carbon nanotubes with nano ferrites and incorporating them into Nano composites are presented .The application of these materials and variation of properties in Nano composites are analysed,in the light of data from literature .

Keywords
Nanocomposites, Carbon Nanotubes, Doping, Chemical Analysis

Author Name

V. Sreenivasulu

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Paper Title

An overview on recent advancements in pulsating heat pipe

Abstract
The Oscillating heat pipe also known as pulsating heat pipe (PHP), one of the most reliable and efficient heat transfer devices, was introduced in the 1990s. Pulsating heat pipes have received growing attention from experimental and theoretical researchers in recent times. Pulsating heat pipes (PHPs) have emerged as interesting alternatives to conventional heat transfer technologies. These simple looking devices have intriguing thermo-hydrodynamic operational characteristics. Heat pipes are heat transfer devices that enhances large amount of heat which works on the principle of evaporation and condensation of a working fluid. Inspite of wide application of heat pipe in microelectronics cooling system the trend of the chips performance and power utilization has been increased each year and a complete understanding of mechanism has not yet been completed even though it has the ability to operate against gravity and a greater maximum heat transport capability. Recent literature suggests that important milestones have been achieved in characterization of these devices. Yet, the very definition of PHPs is quite vague. The aspects of fluid distribution, measurement of fluid oscillations, selection of the optimal working fluid and optimal filling ratio is to be investigated based on the applications of equipment.

Development of indirect resistance spot welding for automotive application

Abstract
Weldment characteristics of resistance spot welding process like weld force, time, current, hardness of the HAZ/ nugget, tension - shear strength and micro and macro structure. They are very impartent parameters to predict the joint strength of lap joint for direct and indirect spot welding process is used for fabrication throughout the world for its simplicity and versality. In this present work developed the indirect resistance spot welding process for cold rolled carbon steel sheet, the fabrication and trials are conducted for both direct and indirect resistance welding and analyzed the parameters of the tension shear breaking load ,nugget diameter, hardness, macro and micro structure and weldabilty lobe.

Keywords
Welding, Resistance spot welding, Mechanical properties

Author Name

Swadesh Kumar Singh

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Paper Title

Study of Formability in Warm Forming of Aluminum IS 737 Alloy

Abstract
Deep Drawing at elevated temperature is becoming very popular due to its advantages over conventional deep drawing. Experimental investigations of warm forming of IS 737 Aluminum alloys are presented in this paper. It is found out that under warm condition there is significant improvement in limiting draw ratio (LDR) of Al alloy which are otherwise very poorly formable. It is observed that LDR for this commercial Al increased from 1.85 at room temperature to 2.46 at 400C. Determination of reliable friction data associated with a given lubrication system is also important for successful process design and simulation by FE analysis. Especially when the deep drawing operation is being performed under warm conditions, the prediction of friction becomes complex as its value increases with temperature. This paper presents a practical methodology that uses the deep drawing test and finite element (FE) analysis to evaluate the coefficient of friction between blank and tooling by inverse analysis of matching the predicted and measured values of the load-stroke curve.

Keywords
Forming, Stamping and Punching, Plastic behavior.

Author Name

R. R. Kharade

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Paper Title

Tuning of optical band gap and structural features of single phase Ag2WO4 thin films: A hybrid synthesis

Abstract
A hybrid physico-chemical route of synthesis was employed for deposition of Ag2WO4 thin films. The WO3 thin film prepared by microwave assisted sol gel synthesis was used as substrates and onto surface of this sterling silver is evaporated at the deposition rate of 20 A/Sec. The prepared samples after annealing at 400°C were characterized for their optical and structural studies. The optical absorption studies reveal tuning of optical band gap from 3.80 eV to 3.54 eV because of Surface Plasmon Resonance (SPR) shown by silver nanoparticles. The X-ray diffraction studies show formation of Ag2WO4 phase with hexagonal system. The electrical resistivity measurements of these films show two different types of conduction mechanisms at low and high temperature. The value of activation energy for Ag2WO4 thin films at low temperature and at high temperature are 0.3469 eV and 1.318 eV respectively. The optical and structural characterizations establish the applicability of Ag2WO4 thin films for electrochromic device.